We present spectral analysis of ASCA data of 17 elliptical and three lenticular galaxies most of which have high Lx/LB. Single-temperature models (mekal and Raymond–Smith) give unacceptable fits (χ2red > 1.5 in most cases and, in agreement with previous studies, give very subsolar abundances, 〈 Z〉 = 0.19 ± 0.12 Z⊙ (mekal). The spectra for approximately half the sample are fitted better by a cooling-flow model, which in three cases gives a substantially better fit. The abundances derived from the cooling-flow model are also significantly larger, 〈Z〉 = 0.6 ± 0.5 Z⊙. We empirically tested the reliability of the plasma codes in the Fe L region and found no evidence for serious problems with the determined temperatures and abundances. Two-temperature models give substantially better fits that are formally acceptable (χ2red ∼ 1.0) in all but a few cases. The highest signal-to-noise ratio galaxies (which also have highest Lx/LB) have fitted temperatures < 2 keV for both components consistent with each being distinct phases of hot gas. The lowest signal-to-noise ratio galaxies (which also have lowest Lx/LB) generally have a hot component with temperature, TH ≳ 5 keV, which is consistent with emission from discrete sources. (We discuss the origin of these two components from analysis of Lx − LB and Lx/LB.) The abundances of these two-temperature models are approximately solar, 〈Z〉 = 0.9 ± 0.7 Z⊙ (mekal), consistent with a recent multiphase model for the evolution of hot gas in ellipticals. Finally, for several galaxies we find evidence for absorption in excess of the Galactic value and discuss its implications.
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Buote et al. (1998) studied this question.